Cancel the request when URLLoader is gone

content/browser/loader/mojo_async_resource_handler.cc

Index: content/browser/loader/mojo_async_resource_handler.cc
diff --git a/content/browser/loader/mojo_async_resource_handler.cc b/content/browser/loader/mojo_async_resource_handler.cc
index b66c389d3ff84b0a3af098cafe9dfbf060f2c835..a2957c0778db2ac7dbbadf764b3f010a906c9f29 100644
--- a/content/browser/loader/mojo_async_resource_handler.cc
+++ b/content/browser/loader/mojo_async_resource_handler.cc
@@ -16,6 +16,7 @@
 #include "content/browser/loader/resource_dispatcher_host_impl.h"
 #include "content/browser/loader/resource_request_info_impl.h"
 #include "content/common/resource_request_completion_status.h"
+#include "content/public/browser/global_request_id.h"
 #include "content/public/browser/resource_dispatcher_host_delegate.h"
 #include "content/public/common/resource_response.h"
 #include "mojo/public/c/system/data_pipe.h"
@@ -238,7 +239,9 @@ void MojoAsyncResourceHandler::FollowRedirect() {
 }
 
 void MojoAsyncResourceHandler::Cancel() {
-  NOTIMPLEMENTED();
+  const ResourceRequestInfoImpl* info = GetRequestInfo();
+  ResourceDispatcherHostImpl::Get()->CancelRequestFromRenderer(
+      GlobalRequestID(info->GetChildID(), info->GetRequestID()));
 }
 
 void MojoAsyncResourceHandler::ResumeForTesting() {